Prom 31 seems to have been loosely based around a royal theme, with two of several nods at this year’s Proms to the Coronation anniversary: explicitly, in the case of William Walton’s Orb and Sceptre march, which he wrote for the 1953 ceremony, and obliquely by way of Edmund Rubbra’s Ode to the Queen, which the BBC commissioned for the Coronation celebrations.